Childhood sexual abuse predicts treatment outcome in conversion disorder/functional neurological disorder. An observational longitudinal study

OBJECTIVE: Explore trauma, stress, and other predictive factors for treatment outcome in conversion disorder/functional neurological disorder (CD/FND). METHODS: Prospective observational design. Clinical cohort study among consecutive outpatients with DSM-IV CD/FND in a specialized mental health institution for somatic symptom disorders and related disorders (SSRD), presented between 1 February 2010 and 31 December 2017. Patient files were assessed for early childhood trauma, childhood sexual abuse, current stress, and other predictive factors. Patient-related routine outcome monitoring (PROM) data were evaluated for treatment outcome at physical (Patient Health Questionnaire [PHQ15], Physical Symptoms Questionnaire [PSQ]) level as primary outcome, and depression (Patient Health Questionnaire [PHQ9]), anxiety (General Anxiety Disorder [GAD7]), general functioning (Short Form 36 Health Survey [SF36]), and pain (Brief Pain Inventory [BPI]) as secondary outcome. RESULTS: A total of 64 outpatients were included in the study. 70.3% of the sample reported childhood trauma and 64.1% a recent life event. Mean scores of patients proceeding to treatment improved. Sexual abuse in childhood (F(1, 28) = 30.068, β = 0.608 p < .001) was significantly associated with worse physical (PHQ15, PSQ) treatment outcome. 42.2% reported comorbid depression, and this was significantly associated with worse concomitant depressive (PHQ9) (F[1, 39] = 11.526, β = 0.478, p = .002) and anxiety (GAD7) (F[1,34] = 7.950, β = 0.435, p = .008) outcome. CONCLUSION: Childhood sexual abuse is significantly associated with poor treatment outcome in CD/FND. Randomized clinical trials evaluating treatment models addressing childhood sexual abuse in CD are needed.